Systems and methods for controlling communication between a host computer and communication devices

ABSTRACT

A site controller adapted to be used in an automated monitoring system for monitoring and controlling a plurality of remote devices via a host computer connected to a first communication network is provided. The site controller is configured for controlling communication with the host computer and a plurality of communication devices that define a second communication network associated with the plurality of remote devices. Briefly described, in one embodiment, the site controller comprises a transceiver configured to communicate with the plurality of communication devices via the second communication network; a network interface device configured to communicate with the host computer via the first communication network; and logic configured to: manage communication with each of the plurality of communication devices, via a first communication protocol; and manage communication with the host computer via a second communication protocol.

CROSS-REFERENCE TO RELATED APPLICATIONS & PRIORITY CLAIM

This application is a continuation of U.S. patent application Ser. No.09/925,786 Filed Aug. 9, 2001 (now U.S. Pat. No. 7,650,425), which is acontinuation-in-part of the following U.S. utility patent applications:U.S. patent application Ser. No. 09/271,517, filed Mar. 18, 1999, nowabandoned and entitled, “System For Monitoring Conditions in aResidential Living Community;” U.S. patent application Ser. No.09/439,059, filed Nov. 12, 1999, now U.S. Pat. No. 6,437,692 andentitled, “System and Method for Monitoring and Controlling RemoteDevices;” U.S. patent application Ser. No. 09/812,809, filed Mar. 20,2001, now abandoned and entitled, “System and Method for Monitoring theLight Level in a Lighted Area,” which is a continuation-in-part of U.S.patent application Ser. No. 09/412,895, filed Oct. 5, 1999, now U.S.Pat. No. 6,218,953 and entitled, “System For Monitoring the Light LevelAround and ATM. U.S. patent application Ser. No. 09/925,786 claimspriority to U.S. Provisional Application No. 60/223,943, filed Aug. 9,2000, and entitled “Design Specifications for a Site Controller,” whichis hereby incorporated by reference in its entirety. Each of theabove-identified applications and patents are incorporated herein byreference as if fully set forth below in their entireties.

TECHNICAL FIELD

The present invention generally relates to systems for monitoring and/orcontrolling a plurality of remote devices via a host computer connectedto a wide area network (WAN), and more particularly relates to systemsand methods for managing communication between the host computer and theplurality of remote devices.

BACKGROUND

There are a variety of systems for monitoring and/or controlling any ofa number of systems and/or processes, such as, for example,manufacturing processes, inventory systems, emergency control systems,personal security systems, residential systems, and electric utilitymeters to name a few. In many of these “automated monitoring systems,” ahost computer in communication with a wide area network monitors and/orcontrols a plurality of remote devices arranged within a geographicalregion. The plurality of remote devices typically use remote sensors andcontrollers to monitor and respond to various system parameters to reachdesired results. A number of automated monitoring systems use computersor dedicated microprocessors in association with appropriate software toprocess system inputs, model system responses, and control actuators toimplement corrections within a system.

Various schemes have been proposed to facilitate communication betweenthe host computer and the remote devices within the system, including RFtransmission, light transmission (including infra-red), and controlsignal modulation over the local power distribution network. Forexample, U.S. Pat. No. 4,697,166 to Warnagiris et al. describes apower-line carrier backbone for inter-element communications. Asrecognized in U.S. Pat. No. 5,471,190 to Zimmerman, there is a growinginterest in home automation systems and products that facilitate suchsystems. One system, critically described in the Zimmerman patent, isthe X-10 system. Recognizing that consumers will soon demandinteroperability between household systems, appliances, and computingdevices, the Electronics Industry Association (EIA) has adopted anindustry standard, known as the Consumer Electronics Bus (CEBus). TheCEBus is designed to provide reliable communications between suitablyconfigured residential devices through a multi-transmission mediaapproach within a single residence.

One problem with expanding the use of control systems technology todistributed systems is the cost associated with developing the localsensor-actuator infrastructure necessary to interconnect the variousdevices. A typical approach to implementing control system technology isto install a local network of hard-wired sensors and actuators alongwith a local controller. Not only is there expense associated withdeveloping and installing appropriate sensors and actuators, but theadded expense of connecting functional sensors and actuators with thelocal controller is also problematic. Another prohibitive cost is theexpense associated with the installation and operational expenseassociated with programming the local controller.

Accordingly, an alternative solution for implementing a distributedcontrol system suitable for monitoring and controlling remote devicesthat overcomes the shortcomings of the prior art is desired.

SUMMARY OF EXEMPLARY EMBODIMENTS

To achieve the advantages and novel features, an embodiment of thepresent invention is generally directed to a cost-effective automatedmonitoring system and method for monitoring and controlling a pluralityof remote devices via a host computer connected to a communicationnetwork, such as a wide area network. The automated monitoring systemmay include one or more sensors to be read and/or actuators to becontrolled, ultimately, through a remote applications server via a sitecontroller. The remote applications server and the site controller maycommunicate via a communication network, such as a wide area network.The sensors and/or actuators are in communication with communicationdevices, which may be wireless that transmit and/or receive encoded dataand control signals to and from the site controller. Additionalcommunication devices, such as wireless repeaters, may relay informationbetween communication devices disposed in connection with the sensorsand/or actuators and the site controller.

More specifically, the present invention is directed to a sitecontroller adapted to be used in an automated monitoring system formonitoring and controlling a plurality of remote devices via a hostcomputer connected to a first communication network. The site controlleris ‘1’ configured for controlling communication with the host computerand a plurality of communication devices that define a secondcommunication network associated with the plurality of remote devices.Briefly described, in one embodiment, the site controller comprises atransceiver configured to communicate with the plurality ofcommunication devices via the second communication network; a networkinterface device configured to communicate with the host computer viathe first communication network; and logic configured to: managecommunication with each of the plurality of communication devices, via afirst communication protocol, based on one or more communication pathsfor each of the plurality of communication devices, each communicationpath comprising one or more communication devices involved in thecommunication link between the transceiver and each of the plurality ofcommunication devices; and manage communication with the host computervia a second communication protocol.

The present invention may also be viewed as providing a method forcontrolling communication with a host computer connected to a firstcommunication network and a plurality of communication devices thatdefine a second communication network associated with a plurality ofremote devices that are to be monitored and controlled by the hostcomputer. Briefly, one such method involves the steps of: determining aunique address for each of the plurality of communication devices byreceiving an initialization message; determining with which of theplurality of communications devices that each of the plurality ofcommunication devices has a communication link; based on the pluralityof unique addresses and which of the plurality of communications deviceseach of the plurality of communication devices has a communication linkwith, determining one or more communication paths associated with eachof the plurality of communication devices; managing communication witheach of the plurality of communication devices, via a firstcommunication protocol, based on one or more of the communication pathsassociated with each of the plurality of communication devices; andmanaging communication with the host computer via a second communicationprotocol.

Thus, the site controller according to the present invention minimizescost and complexity by providing a site controller to maintain the bulkof the data needed by the user and by providing simplified andinexpensive communication devices to collect and communicate the data tothe site controller. By simplifying the communication devices andmaintaining data storage, data organization, etc., at the sitecontroller, initial installation costs are reduced, and futureexpansions of the automated monitoring system are simple andinexpensive.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings incorporated in and forming a part of thespecification, illustrate several aspects of the present invention, andtogether with the description serve to explain the principles of theinvention. The components in the drawings are not necessarily to scale,emphasis instead being placed upon clearly illustrating the principlesof the present invention. Moreover, in the drawings, like referencenumerals designate corresponding parts throughout the several views.

FIG. 1 is a block diagram illustrating an embodiment of an automatedmonitoring system according to the present invention.

FIG. 2 is a block diagram illustrating an embodiment of the sitecontroller of the automated monitoring system of FIG. 1.

FIG. 3 is a more detailed schematic diagram illustrating theconnectivity of the WAN of FIG. 1.

FIG. 4 is a table illustrating an embodiment of a message structure fora communication protocol according to the present invention that may beused for communicating between the site controller and transceivers ofFIG. 1.

FIG. 5 is a table illustrating various values for the “to address” inthe message structure of FIG. 4.

FIG. 6 illustrates three sample messages for the message structure ofFIG. 4 according to the present invention.

FIG. 7 illustrates another embodiment of the automated monitoring systemaccording to the present invention.

DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS

Having summarized the invention above, reference is now made in detailto the description of the invention as illustrated in the drawings.While the invention will be described in connection with these drawings,there is no intent to limit it to the embodiment or embodimentsdisclosed therein. On the contrary, the intent is to cover allalternatives, modifications and equivalents included within the spiritand scope of the invention as defined by the appended claims.

FIG. 1 is a block diagram illustrating one of a number of possibleembodiments of an automated monitoring system according to the presentinvention.

Automated monitoring system 100 may comprise one or more applicationsservers 110, a database 115, a wide area network (WAN) 120,transceivers/repeaters 125, sensor/actuators 130, transceivers 135,sensors 140, transmitters 145, and at least one site controller 150.Each of the sensor/actuators 130 30 and sensors 140 is integrated with asuitably configured wireless transceiver/repeater 125, a wirelesstransceiver 135, or wireless transmitter 145. Within the context of thisdocument, a wireless transceiver/repeater 125, a wireless transceiver135, and a wireless transmitter 145 will be referred to as “wirelesscommunication devices.”

Each of the wireless communication devices in automated monitoringsystem 100 is preferably small in size and may be configured to transmita relatively low-power signal, such as, for example a radio frequency(RF) signal. As a result, in some applications, the transmission rangeof a given RF communication device may be relatively limited. Of course,the transmitter power and range may be appropriately designed for thetarget operating environment. As will be appreciated from thedescription that follows, this relatively limited transmission range ofthe wireless communication devices is advantageous and a desirablecharacteristic of automated monitoring system 100. Although the wirelesscommunication devices are depicted without a user interface such as akeypad, etc., in certain embodiments the wireless communication devicesmay be configured with user selectable pushbuttons, switches, analphanumeric keypad, or any other type of user interface device suitablyconfigured with software and/or firmware to accept operator input. Oftenthe wireless communication device will be in communication with a sensor140 or with a sensor/actuator 130, such as a smoke detector, athermostat, a security system, etc. where user selectable inputs may notbe needed.

As illustrated in FIG. 1, the wireless communication devices inautomated monitoring system 100 are geographically arranged such thatthe antenna patterns (not shown) associated with each wirelesscommunication device overlap to create a coverage area 165. In thismanner, automated monitoring system 100 may enable a site controller 150associated with coverage area 165 to communicate with eachsensor/actuator 130 and each sensor 140 via any of a plurality ofpossible communication paths. For instance, site controller 150 maycommunicate with a specific sensor/actuator 130 via a plurality ofdistinct communication paths, each of which are defined by one or morewireless communication devices involved in the communication betweensite controller 150 and the specific sensor/actuator 130. By way ofexample, one of the plurality of possible communication paths mayconsist of a wireless connection from site controller 150 to a wirelesscommunication device associated with the specific sensor/actuator 130.Another possible communication path may consist of wireless connectionfrom site controller 150 to an intermediate wireless communicationdevice and then to the wireless communication device associated with thespecific sensor/actuator 130. Further communication paths may includemultiple intermediate wireless communication devices in the wirelessconnection between site controller 150 and the wireless communicationdevice associated with the specific sensor/actuator 130.

As illustrated in FIG. 1, one or more sensors 140 may communicate withat least one site controller 150 via a wireless transmitter 145, awireless transceiver 135, or a wireless transceiver/repeater 125.Furthermore, one or more sensors,' actuators 130 may communicate with atleast one site controller 150 via a wireless transceiver 135 or awireless transceiver/repeater 125. One of ordinary skill in the art willappreciate that in order to send a command from the applications server110 to a sensor/actuator 130, the wireless communication deviceassociated with e sensors/actuators 130 should be a two-waycommunication device, such as a transceiver. It will also be appreciatedthat one or more sensors/actuators 130 may be in direct communicationwith one or more site controllers 150. It will be further appreciatedthat the communication medium between the one or more sensor/actuators130 and the one or more site controller 150 may be wireless or, forrelatively closely located configurations, a wired communication mediummay be used.

As is further illustrated in FIG. 1, automated monitoring system 100 maycomprise a plurality of stand-alone wireless transceiver/repeaters 125.Each stand-alone wireless transceiver/repeater 125, as well as eachwireless transceiver 135, may be configured to receive one or moreincoming transmissions (transmitted by a remote transmitter 145 ortransceiver 135) and to transmit an outgoing signal. This outgoingsignal may be any wireless transmission signal, such as, for example, alow-power RF transmission signal, or a higher-power RF transmissionsignal. Alternatively, where a wired configured is employed, theoutgoing signal may be transmitted over a conductive wire, fiber opticcable, or other transmission media. One of ordinary skill in the artwill appreciate that if an integrated wireless communication device(e.g., a wireless transmitter 145, a wireless transceiver 135, or awireless transceiver/repeater 125) is located sufficiently close to sitecontroller 150 such that its output signal can be received by at leastone site controller 150, the data transmission signal need not, beprocessed and repeated through either a wireless transceiver/repeater125 or wireless transceivers 135.

One or more site controllers 150 are configured and disposed to receiveremote data transmissions from the various stand-alone wirelesstransceiver/repeaters 125, integrated wireless transmitters 145, or theintegrated wireless transceivers 135. The site controllers 150 may beconfigured to analyze the transmissions received, convert thetransmissions into TCP/IP format, and further communicate the remotedata signal transmissions via WAN 120 to one or more applicationsservers 110 or other devices in communication with WAN 120. One ofordinary skill in the art will appreciate that additional sitecontrollers 150 may function as either a back-up site controller in theevent of a site controller failure or can function as a primary sitecontroller to expand the potential size of coverage area 165 ofautomated monitoring system 100. When implemented as a back-up sitecontroller 150, the second site controller 150 may function when theapplications server 110 detects a site controller failure.Alternatively, the second site controller 150 may function to expand thecapacity of automated monitoring system 100. A single site controller150 may accommodate a predetermined number of wireless communicationdevices. While the number of wireless communication devices may varybased upon individual requirements, in one of a number of embodimentsthere may be approximately 500 wireless communication devices.

By way of example, a second site controller 150 may double the capacityof a 20 single system. Although not shown, additional site controllers150 may be added depending on the specific implementation of automatedmonitoring system 100. The number of wireless communication devicesmanaged by a site controller 150 is limited only by technicalconstraints such as memory, storage space, etc. In addition, the sitecontroller 150 may manage more addresses than devices as some wirelesscommunication devices may have multiple functions such as sensing,repeating, etc. As stated above, automated monitoring system 100includes an applications server 110 in communication with sitecontroller 150 via WAN 120. Applications server 110 may host any of avariety of application specific software depending on the preciseenvironment in which automated monitoring system 100 is employed. Asfurther described below, the site controller 150 may receive, via WAN120, information in the form of data and/or control signals fromapplications server 110, laptop computer 155, workstation 160, and anyother device in communication with WAN 120. Site controller 150 may thencommunicate the data and/or control signals to remote sensor/actuators130 and/or remote sensors 140. Automated monitoring system 100 may alsocomprise a database 115 associated with applications server 110.Database 115 may be configured to communicate with applications server110 and record client specific data or to assist the applications server110 in deciphering a particular data transmission from a particularsensor 140.

FIG. 2 sets forth one of many possible embodiments of the sitecontroller 150 of FIG. 1. Site controller 150 may comprise amicro-controller 205, a power supply 210, an on-site input port 215, anantenna 220, and a transceiver 225. One of ordinary skill in the artwill appreciate that various other elements may be included based on anyof a variety of design needs. The micro-controller 205 may comprise acentral processing unit (CPU) 230, memory 235, and one or more networkinterface devices 240. The CPU 230 may be any of a variety of knowncontrollers, such as, for example, a microprocessor, hard-wiredcircuitry, firmware, etc. The memory 235 may store any necessaryprogramming code for the CPU 230, as well as one or more look 15 uptables 270, databases (not shown), etc. Network interface devices 240may be any of a variety of devices configured for communication with WAN120. For example, site controller 150 may include a network cardconfigured for communication across a local area network to a networkserver. The network server may contain a backup site controller (notshown) coupled to WAN 120 (FIG. 1). Alternatively, site controller 150may include a digital subscriber line (DSL) modem 250 configured toprovide a link to a remote computing system. In yet another alternative,site controller 150 may include an integrated services digital network(ISDN) card configured for communication via an ISDN connection with aremote system. Other network interfaces may be provided to serve asprimary and/or backup links to WAN 120 (FIG. 1) or to local areanetworks (not shown) that might serve to permit local monitoring of theoperating status of site controller 150 and for data packet control.

Depending upon the specific configuration of network interface device(s)240, site controller 150 may communicate with any of a variety of typesof wide area networks. For example, WAN 120 maybe any type ofcommunication network, or collection of communication networks,employing any network topology, transmission medium, or networkprotocol. WAN 120 may be any public or private packet-switched or otherdata network, including the Internet, circuit-switched networks, such asthe public switched telephone network (PSTN), wireless networks, or anyother desired communications infrastructure. One of ordinary skill inthe art will appreciate that the information transmitted between thewireless communication and site controller 150 may be further integratedwith various other data transmission protocols for transmission acrosstelecommunications and computer networks other than the WAN 120 (FIG.1). In addition, it should be further appreciated that communicationnetworks other than WAN 120 (FIG. 1) may function as the transmissionpath between the wireless communication devices, site controller 150,and the applications server 110 (FIG. 1).

Referring again to FIG. 2, wireless transceiver 225 may be configured toreceive incoming transmissions via antenna 220. Each of the incomingtransmissions may be consistently formatted in the message protocol asdescribed below. Site controller 150 may be configured such that thememory 235 includes a look-up table 270 configured for identifying thevarious wireless communication devices (including intermediate wirelesscommunication devices) used in generating and transmitting the receiveddata transmission. As illustrated in FIG. 2, site controller 150 mayinclude an “Identify Remote Transceiver” memory sector 275 and an“Identify Intermediate Transceiver” memory sector 280. Programmed orrecognized codes within the memory 235 may also be provided andconfigured for controlling the operation of a CPU 230 to carry out thevarious functions that are orchestrated and/or controlled by the sitecontroller 150. For example, memory 235 may include program code forcontrolling the operation of the CPU 230 to evaluate an incoming datapacket to determine what action needs to be taken. In this regard, oneor more look-up tables 270 may also be stored within the memory 235 toassist in this process. Function codes and wireless communication deviceidentifiers transmitter may all be stored with associated informationwithin look-up tables 270.

Thus, one look-up table 270 may be provided to associate identificationinformation for each wireless communication device with a particularuser. Another look-up table 270 may be used to identify the variousfunction codes associated with the message protocol. For example, alook-up table 270 may include a unique code designating variousfunctions such as test, temperature, smoke alarm active, security systembreach, etc. One of ordinary skill in the art will appreciate thatvarious function codes may be implemented depending on the specificimplementation of automated monitoring system 100. In connection withlookup table(s) 270, memory 235 may also include one or more codesegments that are executed by the CPU 230 and configured to controloperation of the site controller 150. For example, a first data packetsegment may be configured for accessing a first lookup table todetermine the identity of the wireless communication device thattransmitted the received message to the site controller 150. A secondcode segment may be configured for accessing a second look-up table todetermine the proximate location of the wireless communication devicethat generated the received message. A third code segment may beprovided to identify the content of the message transmitted (not shown).Namely, is it a fire alarm, a security alarm, an emergency request by aperson, a temperature control setting, etc., In accordance with thepresent invention, additional, fewer, or different code segments may beprovided to carry out various functional operations and data signaltransfers.

The power supply 210 may be one of the following: AC power supply. ACpower supply with rechargeable battery as a back up solar cells,battery, etc. The power supply provides appropriate DC voltage levels tomicrocontroller 230. The AC power supply may operate from an external,commonly-provided outside AC power line. The battery may be a lead acidgel battery or other appropriate battery for the prevailingenvironmental and other conditions that could be considered by those ofordinary skill in the art. The battery may maintain the site controller150 fully operational for a predetermined time period. This time periodmay be varied based upon the individual site and system criteria aswould be obvious to one of ordinary skill in the art. The battery mayalso be supplied with a recharger that can recharge the battery to fullcapacity within a predetermined time period. The charging time may bevaried based upon individual site and system criteria as would beobvious to one of ordinary skill in the art. The microcontroller 230 maymonitor the battery on a periodic basis and report the battery conditionto the applications server 110.

In addition, the power supply 210 may accommodate AC voltages betweenapproximately 95-135V. It would be obvious to one of ordinary skill inthe art to modify this supplied voltage range depending upon individualdesigns. For example, the supplied voltage range may be varied toaccommodate any of a variety of standard supply voltages. Furthermore,the power supply 210 may maintain the temperature of site controller 150within an acceptable working range, such as approximately 5° C. abovethe ambient temperature. The operating temperature of the sitecontroller 150 depends upon individual system and environmentalconditions. Therefore, it would be obvious to one of ordinary skill inthe art to maintain the system at an appropriate operating temperature.This can be accomplished by distributing and/or removing the heat fromthe power supply 210, adding a heater or various cooling devices, etc.as known by one of ordinary skill in the art.

The on-site input port 215 may be configured to enable an on-sitetechnician to communicate with the microcontroller 230. By way ofexample, the on-site input port 215 may be a serial port, a USB port,etc. as would be known to one of ordinary skill in the art. Thetechnician may communicate with the on-site input port 215 via any of avariety of computing devices, such as a laptop, personal digitalassistant (PDA), or any other computing device. The on-site input port215 may be used for initial programming updates and other functions asnecessary. In addition to on-site programming via the on-site input port215, the site controller 150 may be reprogrammed via the applicationsserver 110 (FIG. 1).

The transceiver 225 may be a TR1000 hybrid transceiver, which iswell-suited for short range, wireless data applications where robustoperation, small size, power consumption, and low-cost are desired. Allof the critical wireless functions may be contained within the singlehybrid chip to simplify circuit design and accelerate the designprocess. The receiver section of the TR1000 may preferably be sensitiveand stable. A wide dynamic range log detector may be employed, incombination with digital automatic gain control (AGC) to provide robustperformance in the presence of channel noise or interference. Two stagesof surface acoustic wave (SAW) filtering may provide excellent receiverout-of-band rejection. The transmitter may be configured for both on-offkeyed (00K) and amplitude-shift key (ASK) modulation. The transmittermay be configured for employing SAW filtering to suppress outputharmonics in compliance with FCC and other regulations. One of ordinaryskill in the art will appreciate that transceiver 225 may be configuredin a variety of ways. For example, transceiver 225 may include other 900MHz transceivers, as well as transceivers at other frequencies. Inaddition, infrared, ultrasonic, and other types of transceivers may beemployed, consistent with the scope of the present invention.

The antenna 220 radiates the signal transmitted by the transceiver 225to the various wireless communication devices located within coveragearea 165. A specific antenna type may be selected based on the frequencyat which the signal is to be transmitted. In addition, the antenna 220may be adjustably oriented as required to maximize both transmission andsignal characteristics. Non-limiting examples of antenna types that maybe used by the site controller 150 include dipoles, spiral, logarithmic,etc.

The site controller 150 may also be equipped to operate in a wide rangeof temperatures and humidity levels to provide a consistently operatingsystem. In addition, the site controller 150 may be protected fromstatic discharges and direct contact discharges, such as lighteningstrikes. To provide consistent operation, the site controller 150 may beshielded to avoid interference from a wide range of electric field andAC line noise.

Significantly, the site controller 150 may communicate with all of thewireless communication devices. Of further significance, the datamonitoring and control devices need not be disposed in a permanentlocation as long as they remain within signal range of a repeatingwireless communication device that is within signal range of a sitecontroller 150 that is interconnected through one or more communicationnetworks to the applications server 110. Of still further significance,the automated monitoring system 100, as illustrated in FIG. 1, providesa flexible access and control solution through virtually any suitablyconfigured computing device in communication with the WAN 120. By way ofexample, a laptop computer 155 and/or a computer workstation 160appropriately configured with suitable software may provide remoteoperator access to data collected via automated monitoring system 100.In more robust embodiments, the laptop computer 155 and the computerworkstation 160 may permit a user to enter remote operative commands.

In one embodiment of automated monitoring system 100, an applicationsserver 110 (FIG. 1) collects, formats, and stores client specific datafrom each of the integrated wireless transmitters 145, wirelesstransceivers 135, and/or wireless transceiver/repeaters 125 for laterretrieval and/or access from, for example, workstation 160 or laptop155. Workstation 160 or laptop 155 may be used to access the storedinformation in a variety of ways, such as via a web browser. In anotherembodiment, the applications server 110 may host application specificfunctions associated with automated monitoring system 100, therebyreplacing site controller 150 by generating required control signals forappropriate distribution via the WAN 120 and the site controller 120 tothe sensor/actuators 130 and the sensors 140. In a further embodiment,clients may elect, for proprietary reasons, to host control applicationson their own workstation 160 that is connected to WAN 120. In thismanner, database 115 and applications server 110 may function solely asdata collection and reporting devices with the client workstation 160generating control signals for the system.

Reference is now made to FIG. 3, which illustrates the externalconnectivity of WAN 120 of FIG. 1 in accordance with the presentinvention. Site controller 150 may be configured to transmit controlsignals and receive data signals using the open data packet protocoldescribed in detail below. Site controller 150 is preferablyinterconnected permanently on WAN 120 and configured to receive datasignals from the wireless communication devices and translate the datasignals for transfer to applications servers 110 via WAN 120. Sitecontroller 150 may translate the received data signals into anyappropriate protocol for delivery via WAN 120. For example, in oneembodiment site controller 150 translates the received data signals intotransmission control protocol/Internet protocol (TCP/IP) for deliveryvia WAN 120. As stated above, applications server 110 may be configuredfor communication with WAN 120 via, for example, router 310 and furtherprotected and buffered by firewall 320. Applications server 110 may alsoconfigured with web applications and client specific applications asneeded for operation of automated monitoring system 100. Consistent withthe concepts and teachings of the present invention, applications server110 may be assisted in its task of storing and making available clientspecific data by database 115.

As further illustrated in FIG. 3, a client workstation 160 may include aWeb browser for facilitating communication with applications server 110,database 115, and/or site controller 150. Alternatively, clients mayaccess WAN 120 via a remote laptop 155 or other computing devices (notshown) configured with a compatible Web browser or other user interface.In this way, the applications server 110 may provide client specificdata upon demand.

As stated above, communication between site controller 150 and 30sensors/actuators 130 and sensors 140 is accomplished using an open datapacket protocol in accordance with the present invention. Because thewireless communication devices are geographically arranged such thattheir respective antenna patterns overlap to create a coverage area 165,site controller 150 may communicate with each sensor/actuator 130 andeach sensor 140 via any of a plurality of possible communication paths.Each of the communication paths are defined by one or more wirelesscommunication devices involved in the communication between sitecontroller 150 and the target sensor/actuator 130 and/or sensor 140. Forinstance, site controller 150 may communicate with a specificsensor/actuator 130 via a plurality of distinct communication paths. Byway of example, one of the plurality of possible communication paths mayconsist of a wireless connection from site controller 150 to a wirelesscommunication device associated with the specific sensor/actuator 130.Another possible communication path may consist of a wireless connectionfrom site controller 150 to an intermediate wireless communicationdevice and then to the wireless communication device associated with thespecific sensor/actuator 130. Further communication paths may includemultiple intermediate wireless communication devices in the wirelessconnection between site controller 150 and the wireless communicationdevice associated with the specific sensor/actuator 130. In this manner,site controller 150 may communicate with sensors/actuators 130 and/orsensors 140 that are located a greater distance from the site controller150 by having messages repeated by successive wireless communicationdevices along one of the communication paths.

FIG. 4 sets forth a format for the open data packet protocol of thepresent 20 invention. All messages transmitted within automatedmonitoring system 100 consist of a “to” address 400, a “from” address410, a packet number 420, a number of packets in a transmission 430, apacket length 440, a message number 450, a command number 460, datafield 470, and a check sum error detector (CkH 480 and CkL 490).

The “to” address 400 indicates the intended recipient of the packet.This address can be scalable from one to six bytes based upon the sizeand complexity of the system. By way of example, the “to” address 400can indicate a general message to all wireless communication devices, toonly the stand-alone wireless communication devices, or to an individualintegrated wireless communication device. In a six byte “to” address,the first byte indicates the type of the wireless communicationdevice—to all wireless communication devices, to some wirelesscommunication devices, or to a specific wireless communication device.The second byte can be the identification base, and bytes three throughsix can be used for the unique address of the wireless communicationdevice (either stand-alone or integrated). The “to” address 400 isscalable from one byte to six bytes depending upon the intendedrecipient(s).

The “from” address 410 may be the six-byte unique address associatedwith the device from which the transmission originated. The “from”address 410 may be the address of the site controller 150 when the sitecontroller 150 requests data, or this can be the address of one of thewireless communication devices responding to a request for informationfrom the site controller 150.

The packet number 420, the packet maximum 430, and the packet length 440may be used to concatenate messages that are greater than apredetermined byte length. The packet maximum 430 indicates the numberof packets in the message. The packet number 420 may be used to indicatea packet sequence number for a multiple-packet message.

The message number 450 may originally be assigned by the site controller150. Messages originating from the site controller 150 may be assignedan even number, while responses to the site controller 150 may be theoriginal message number plus one, thereby rendering the respondingmessage with an odd number. For example. the site controller 150 mayincrement the message number 450 by two for each new originatingmessage. This enables the site controller to coordinate the incomingresponses to the appropriate command message.

The command number 460 may designate a specific data request from thereceiving device as necessary. One of ordinary skill in the art willappreciate that, depending on the specific implementation of automatedmonitoring system 100, the types of commands may differ. In oneembodiment, there may be two types of commands: device specific and notdevice specific. Device specific commands may control a specific device,such as a data request or a change in current actuator settings.Commands that are not device specific may include, but are not limitedto, a ping, an acknowledgement, a non-acknowledgement, downstreamrepeat, upstream repeat, read status, emergency message, and a requestfor general data to name a few. General data may include a softwareversion number, the number of power failures, the number of resets, etc.

The data field 470 may contain data as requested by a specific command.The requested data may be any value. By way of example, test data maypreferably be encoded in ASCII (American Standard Code for InformationInterchange) or other known encoding systems as known in the art. Thedata field 470 of a single packet may be scalable up to a predeterminedbyte length. When the requested data exceeds the predetermined bytelength, the integrated wireless communication device may divide the datainto an appropriate number of sections and concatenate the series ofpackets for one message using the packet identifiers as discussed above.

The checksum fields 480 and 490 are used to detect errors intransmissions. In one embodiment, any error can be detected via cyclicredundancy check sum methodology. This methodology divides the messageas a large binary number by the generating polynomial (in this case,CRC-16). The remainder of this division is then sent with the message asthe checksum. The receiver then calculates a checksum using the samemethodology and compares the two checksums. If the checksums do notmatch, the packet or message will be ignored. While this error detectionmethodology is preferred, one of ordinary skill in the art willappreciate that various other error detection methodologies may beimplemented.

As stated above, automated monitoring system 100 may employ wirelessand/or wired communication technologies for communication between sitecontroller 150 and the wireless communication devices. In oneembodiment, communication between site controller 150 and the wirelesscommunication devices within coverage area 165 may be implemented usinga wireless link having a basic rate of 4,800 bits per second (bps) and adata rate of 2400 bps. All the data may be encoded in the Manchesterformat such that a high to low transition at the bit center pointrepresents a logic zero and a low to high transition represents a logicone. One of ordinary skill in the art will appreciate that other signalformats may be used as desired. By way of example, a quadature phaseshift encoding method may be used, thereby enabling the site controller150 to communicate via hexadecimal instead of binary. The sitecontroller 150 may use any predetermined RF transmission method totransmit the messages. In one embodiment, a transmission frequency ofapproximately 916.5 MHz may be employed, although one of ordinary skillin the art will appreciate that any other frequency may be desirable.Alternatively, the transmission can be on a predetermined range offrequencies such as with spread spectrum technology. Furthermore, themessage may be modulated using any technique, such as on-off keying,frequency modulation (FM), or any other modulation technique.

While the message indicates the specific byte length for each section,only the order of the specific information within the message isconstant. The byte position number in individual transmissions may varybecause of the scalability of “to” address 400, command number 460, andthe scalability of data field 470.

The message may further include a preface and a postscript (not shown).The preface and postscripts need not be part of the message body, butrather provide synchronization and frame each packet of the message. Thepacket may begin with the preface and end with the postscript. Thepreface may be, for example, a series of twenty-four logic ones followedby two bit times of high voltage with no transition.

The first byte of the packet may then follow immediately. The postscriptmay be, for example, a transition of the transmit data line from a highvoltage to a low voltage. It may be less desirable to not leave thetransmit data line high after the message is sent. Furthermore, one ofordinary skill in the art will appreciate that the preface andpostscript may be modified in a number of ways.

FIG. 5 sets illustrates one embodiment of a byte assignment for the “to”address 400 of FIG. 4. One of ordinary skill in the art will appreciatethat various byte assignments may be used within “to” address field 400.For example, in one embodiment, “to” address 400 consists of six bytes.The first byte (Byte 1) may indicate the device type. The second byte(Byte 2) may indicate the manufacturer or the owner. The third byte(Byte 3) may be a further indication of the manufacturer or owner. Thefourth byte (Byte 4) may indicate either that the message is for alldevices or that the message is for a particular device. If the messageis for all devices, the fourth by may be a particular code. If themessage is for a particular device, the fourth, fifth, and sixth bytes(Byte 5 and Byte 6) may include the unique identifier for thatparticular device.

Having described the general message structure for the open data packetprotocol of the present invention, reference is directed to FIG. 6,which illustrates three sample messages. The first message 600illustrates the broadcast of an emergency message “FF” from a centralserver with an address “0012345678” to a integrated transceiver with anaddress of “FF.”

The second message 602 illustrates how the first message 600 may be sentto a stand-alone wireless communication device. In this manner,emergency message FF″ from a central server with address “00123456578”is first sent to stand-alone wireless device “FO.” The second message602, further contains additional command data “A000 123456” that may beused by the wireless communication device to identify further wirelesscommunication devices to send the signal through on the way to thedestination device.

The third message 604 illustrates how the open data packet protocol ofthe present invention may be used to “ping” a remote wirelesscommunication device in order to determine the status of the wirelesscommunication device. In this manner, source unit “E112345678”originates a ping request by sending command “08” to a transceiveridentified as “A012345678.” The response to the ping request may be assimple as reversing the “to address” and the “from address” of thecommand such that a healthy wireless communication device may send aping message back to the originating device. Automated monitoring system100 may be configured to expect a return ping within a specific timeperiod. Operators of automated monitoring system 100 may use the delaybetween the ping request and the ping response to model system loads andto determine if specific system parameters might be adequately monitoredand controlled with the expected feedback transmission delay.

Further information regarding the structure and operation of the datapacket protocol implemented in automated monitoring system 100 may befound in commonly assigned U.S. Patent Application “System and Methodfor Interconnecting Remote Devices in an Automated Monitoring System,”U.S. patent application Ser. No. 09/925,445, which is herebyincorporated in its entirety by reference.

Referring again to FIG. 1, during normal operations, the site controller150 acts as the communications master. Thus, the site controller 150 mayinitiate all communications with the wireless communications devices,except emergency messages described below. In addition to initiatingcommand messages, the site controller 150 also tracks response messages.This tracking allows the site controller 150 to monitor the operationalstatus of the wireless communication devices.

In addition to orchestrating communications with the wirelesscommunication 30 devices, the site controller 150 maintains currentdatabases of information regarding the automated monitoring system 100,such as, for example, the function of the wireless communicationdevices, the unique address for each of the wireless communicationdevices, and current data contained in response messages. One ofordinary skill in the art will appreciate that site controller 150 maycontain information related to any of a variety of other aspects ofautomated monitoring system 100.

As stated above, the site controller 150 also controls communicationswith the applications server 110. When communicating with theapplications server 110, the site controller 150 receives requests forinformation, commands, etc. and sends the appropriate response. Theapplications server 110 maintains the requested information and/orcommands in such a way that a user can access the information via aremote desktop 155, remote laptop 160, or any other device configuredfor communication with WAN 120.

Furthermore, the site controller 150 may be configured to maintain adatabase of the wireless communication devices and their uniqueaddresses. The unique addresses may be assigned such that the sitecontroller 150 may easily send messages to one wireless communicationdevice, a group of wireless communication devices, or all of thewireless communication devices.

Using the site controller 150 as a communications master and maintainingindividual device information at the site controller 150 enables thewireless communication devices to be simplified. The simplification ofthe wireless communication devices has two main advantages: (1)simplifying the construction of the wireless communication device and(2) decreasing cost. The wireless communication device may be simplifiedbecause of a reduced need for large memory and/or storage devices. Aswell-known in the art, memory and storage devices increase in cost asthey increase in size. Therefore, decreasing the size of the memoryand/or storage reduces the construction and operating costs of thewireless communication devices.

The site controller 150 sends messages to the wireless communicationdevices using the open data packet protocol described above. Initially,the site controller 150 maps all of the wireless communication devicesso as to “learn” all the unique addresses and the necessarycommunication paths. To do this mapping, the site controller 150 issuesa command to document the down-stream addresses and the up-streamaddresses for each communication path associated with a wirelesscommunication device. The site controller 150 logs the response datafrom the wireless communication devices into the appropriate databases.Messages from the site controller 150 travel downstream to the intendedwireless communication device(s). Messages from the wirelesscommunication devices(s) travel upstream to the site controller 150.When mapping the communication paths for each of the wirelesscommunication devices, the site controller 150 “learns” the uniqueaddress of each wireless communication device, the addresses of eachwireless communication device that can directly and reliably communicatewith each transceiver/repeater(s) 125 in a downstream path, the uniqueaddress of each transceiver/repeater(s) 125 in a downstream path, theupstream addresses for the wireless communication device, and thedownstream addresses for the wireless communication device.

When sending command messages, the site controller 150 expects anacknowledgement to each command. A command is considered to be notacknowledged when either the site controller 150 fails to receive apositive acknowledgement from the addressed wireless communicationdevice within a first time period, fails to detect the re-transmissionof the command message by a transceiver/repeater 125 within a secondtime period, or receives a negative acknowledgement from atransceiver/repeater 125 in the communication path of the wirelesscommunication device. If the site controller 150 receives a negativeacknowledgement, the site controller 150 can then log the failed messageand retransmit the message. This re-transmission can occur apredetermined number of times. It should be noted the first time periodmay be longer than the second time period. In the above cases, the firsttime period is long enough to ensure receipt of the preamble of theresponse message when there are multiple transceiver/repeater(s) 125 inthe communications path. The second time period is long enough to eitherreceive the preamble of the response message (if no repeaters are in thecommunications path) or to hear the preamble of the command messagebeing re-transmitted by the first transceiver/repeater 125 in thecommunication path of the wireless communication device.

After initializing and during normal operation, the site controller 150may poll each of the remote sensor/actuators according to apredetermined schedule. During this process, the site controller 150requests the current operating status of each of the sensors/actuators135. The status of a sensor/actuator device 135 depends upon the type ofdevice. For example, a smoke detector's status may be operational/nonoperational. In contrast, a utility meter's status may be the utilityusage that has occurred since the last polling. A thermostat's statusresponse may be the actual temperature and the desired temperature. Theinformation sent in response to a status poll may vary depending uponthe particular configuration of the sensor/actuator 135. Thisinformation is maintained by the site controller 150 and may be sent tothe applications server 110 upon request. The predetermined schedule hasflexibility based upon the number of failed attempts and any emergencymessages. To poll the device, the site controller 150 sends a “readstatus” message. The command message is considered complete upon receiptof the response message. The command message is considered failed uponreceipt of a negative acknowledgement. After a negative acknowledgement,the site controller 150 retries the command six more times and logs allfailed attempts.

To facilitate communications with the applications server 110, the sitecontroller 150 may maintain database files of information. The sitecontroller 150 may maintain communication databases that store thedevice failures, as discussed above. and that store the emergencymessages. These database stored logs can contain the unique address ofthe wireless communication device, a code representing a presentcondition, and a date/time stamp. Any failures to communicate with theapplications server 110 are also logged into the appropriate database.These databases may have a predetermined size and may be forwarded tothe applications server 110 when the databases are a specific percentagefull or upon request by the applications server 110.

Once forwarded to and acknowledged by the applications server 110, theentries in the communications databases are deleted. One of ordinaryskill in the art will appreciate that the contents, size, and schedulingof database entries may be varied in a variety of ways.

After mapping the wireless communication devices, the site controller150 develops and maintains a database that includes the unique addressfor each wireless communication device, the number oftransceiver/repeaters 125 in the downstream path, the address of eachtransceiver/repeater 125 in the downstream path, the upstream addresses,and the downstream addresses. The site controller 150 does notnecessarily respond to the messages from wireless communication device snot listed in this database.

In addition to mapping the wireless communication devices, the sitecontroller 150 may update the device database via the applicationsserver 110. This update may add/delete wireless communication devicesfrom the automated monitoring system 100, change the communications pathof any or all of the wireless communication devices, or change theunique addresses of any or all of the wireless communication devices.Upon request of the applications server 110, the site controller 150 maytransmit the device database to the applications server 110.

It should be noted that the databases enumerated above are merelyexemplary, and other databases may be included as would be obvious toone of ordinary skill in the art.

The “normal” operating procedure described above is continued unless thesite controller 150 receives an emergency message from a wirelesscommunication device. The emergency message is transmitted unsolicited.The emergency message can be received by the site controller 150 eitherdirectly, via a repeater, or via a plurality of repeaters. Upon receiptof an emergency message, the site controller 150 immediately notifiesthe applications server 110 of the emergency message. In addition, thesite controller 150 suspends the above polling for a predetermined timeperiod. This suspension insures the receipt of any additional emergencymessages. After the time period expires with no additional messages, thesite controller 150 resumes polling.

To facilitate communications between the applications server 110 and thesite controller 150, the site controller 110 maintains a database ofcontact information. By way of example, if the site controller 150communicates via a network interface device 240, the site controller 150can maintain a database of telephone numbers and IP addresses of theapplications server 110.

During normal communications, the applications server 110 sends responsemessages. As stated above, one of ordinary skill in the alt willappreciate that the applications server 110 and the site controller 150may communicate via TCP/IP protocol or any other protocol. Exemplaryrequests include a “get file” request of the database and a “put file”request, which sends a file to the site controller 150.

Normal communications between the site controller 150 and theapplications server 110 may also be interrupted by an emergency message.The emergency message originates at the site controller 150 and mayinclude an emergency message from a remote device, a “file too large”message, and a site controller status change message to name a few. Inthe case of safety and security system devices such as smoke detectors,glass break alarms, etc., the site controller 150 may immediatelygenerate an emergency message to the applications server 110 in theevent a safety/security device fails to respond to a poll message.

One of ordinary skill in the art will appreciate that what has beendescribed herein is a very top-level illustration of a systemconstructed in accordance with the automated monitoring system 100 ofthe present invention. In accordance with the invention, a variety ofremote devices, such as utility meter devices, personal securitydevices, household devices and appliances, and other remote devicesemploying a sensor and/or an actuator, may be monitored and/orcontrolled from a remote location via a computing device connected toWAN 120. The data and command transmissions may be transmitted andreceived by the site controller 150 connected to WAN 120, Sitecontroller 150 is further in communication with the wirelesscommunication devices within coverage area 165. The data and commandtransmissions may be relayed via the various wireless communicationdevices defining the communication path until they reach a designateddestination or the site controller 150.

It will be further appreciated that automated monitoring system 100 inaccordance with the present invention may be used in a variety ofenvironments. In one embodiment, automated monitoring system 100 may beemployed to monitor and record utility usage by residential andindustrial customers, to transfer vehicle diagnostics from an automobilevia a wireless transceiver integrated with the vehicle diagnostics busto a local transceiver that further transmits the vehicle informationthrough a local gateway onto a WAN, to monitor and control an irrigationsystem, to automate a parking facility, to monitor and control aresidential security system, etc, which are described in more detail inthe commonly assigned U.S. patent application entitled, “System andMethod for Monitoring and Controlling Residential Devices,” issued Ser.No. 09/704,150.

Automated monitoring system 100 may be adapted to monitor and applycontrol signals in an unlimited number of applications. By way ofexample only, the wireless communication devices may be adapted for usewith any associated device, such as, for example, pay type publiclylocated telephones, cable television set top boxes, utility meters, andresidential appliances and/or devices to enable a remote controllablehome automation and security system.

In a geographic area appropriately networked with permanently locatedstand alone transceivers 125, personal transceivers (not shown) may beused to monitor and control personnel access and egress from specificrooms or portions thereof within a controlled facility. Personaltransceivers may further be configured to transfer personal informationto public emergency response personnel, to transfer personal billinginformation to vending machines, or to monitor individuals within anassisted living community.

Wireless communication devices using the open data packet protocol ofthe present invention may be integrated to monitor and control a host ofindustrial and business applications as well. By way of example only,building automation systems, fire control systems, alarm systems,industrial trash compactors, and building elevators may be monitored andcontrolled. In addition, courier drop boxes, time clock systems,automated teller machines, self-service copy machines, and otherself-service devices may be monitored and controlled as appropriate. Byway of further example, a number of environment variables that requiremonitoring may be integrated with automated monitoring system 100 topermit remote monitoring and control. For instance, light levels in thearea adjacent to automated teller machines must meet minimum federalstandards. Also, the water volume transferred by water treatment plantpumps, smokestack emissions from a coal burning power plant, or a cokefueled steel plant oven may be remotely monitored.

The wireless communication devices using the open data packet protocolof the present invention may be further integrated with a voice-bandtransceiver having multiple function buttons. As a result, when a personpresses, for example, the emergency button on his/her transmitter,medical personnel, staff members, or others may respond by communicatingvia two-way radio with the party in distress. In this regard, eachtransceiver may be equipped with a microphone and a speaker that wouldallow a person to communicate information such as their presentemergency situation, their specific location, etc.

As an example, FIG. 7 sets forth an alternate embodiment of an automatedmonitoring system 100. Automated monitoring system 100 of FIG. 1 isshown with an additional sensor 180 and transceiver 185. The additionalsensor 180 and transceiver 185 are shown to be communicating with, butoutside of, the coverage area 165. In this example, the additionalsensor 180 and transceiver 185 may be placed outside of the originalcontrol system. In order to communicate, the coverage area oftransceiver 185 need only overlap the coverage area 165. By way ofexample only, the original installation may be an automated monitoringsystem 100 that monitors electricity usage via the utility meters in anapartment complex. Later a neighbor in a single family residence nearbythe apartment complex may remotely monitor and control their thermostatby installing a sensor/actuator transceiver according to the presentinvention. The transceiver 185 then communicates with the sitecontroller 150 of the apartment complex. If necessary, repeaters (notshown) can also be installed to communicate between the transceiver 185and the apartment complex site controller 150. Without having the costof the site controller 150, the neighbor may enjoy the benefits of thecontrol system.

The foregoing description has been presented for purposes ofillustration and description. It is not intended to be exhaustive or tolimit the invention to the precise forms disclosed. Obviousmodifications or variations are possible in light of the aboveteachings. For example, it should be appreciated that, in someimplementations, the transceiver unique address is not necessary toidentify the location of the transceiver. Indeed, in implementationswhere the transceiver is permanently integrated into an alarm sensorother stationary device within a system, then the applications server110 and/or the site controller 150 may be configured to identify thetransmitter location by the transmitter unique address alone. It will beappreciated that, in embodiments that do not utilize wirelesstransceiver/repeaters 125, the wireless transmitters 145 and/or wirelesstransceivers 135 may be configured to transmit at a higher power level,in order to effectively communicate with the site controller 150.

The embodiment or embodiments discussed were chosen and described toillustrate the principles of the invention and its practical applicationto enable one of ordinary skill in the art to utilize the invention invarious embodiments and with various modifications as are suited to theparticular use contemplated. All such modifications and variations arewithin the scope of the invention as determined by the appended claimswhen interpreted in accordance with the breadth to which they are fairlyand legally entitled.

The invention claimed is:
 1. A site controller adapted to be used in anautomated monitoring system configured for monitoring and controlling aplurality of remote devices via a host computer connected to a firstcommunication network, the site controller configured for controllingcommunication with the host computer and a plurality of communicationdevices that define a second communication network associated with theplurality of remote devices, wherein the second communication networkcomprises a first communication device associated with a first remotedevice and a second communication device associated with a second remotedevice, the site controller comprising: a transceiver configured tocommunicate with the plurality of communication devices via the secondcommunication network; a network interface device configured tocommunicate with the host computer via the first communication network;and logic configured to: manage communication with each of the pluralityof communication devices, via a first communication protocol, based onone or more communication paths for each of the plurality ofcommunication devices and the identification of each of the plurality ofcommunication devices in the one or more communication paths, eachcommunication path comprising one or more communication devices involvedin the communication link between the transceiver and each of theplurality of communication devices, wherein the communication path forthe second communication device comprises the first communicationdevice; manage communication with the host computer via a secondcommunication protocol; poll one or more of the remote devices accordingto a predetermined schedule by transmitting a status message to one ormore remote devices requesting current operating status of the remotedevice, wherein the operating status comprises information indicative ofa condition monitored or controlled by the remote device independent ofother remote devices and communication devices, and determine and storeupstream and downstream communication paths for each of the plurality ofcommunication devices in the second communication network.
 2. The sitecontroller of claim 1, wherein the logic is software and furthercomprising a microcontroller for implementing the logic.
 3. The sitecontroller of claim 1, wherein each of the plurality of communicationdevices are wireless communication devices, the plurality of wirelesscommunication devices being disposed throughout a geographic area suchthat the antenna patterns associated with the plurality of wirelesscommunication devices overlap to create a coverage area that defines thesecond communication network.
 4. The site controller of claim 1, whereinthe first communication network is a wide area network and the secondcommunication protocol comprises TCP/IP.
 5. The site controller of claim1, wherein the first communication protocol comprises a data packet, thedata packet comprising: a to address; a from address; and a commandnumber comprising a function code.
 6. The site controller of claim 5,wherein the data packet further comprises: a data field; a checksumfield; a packet number field; a packet length field; a packet maximumfield; and a message number field.
 7. The site controller of claim 1,wherein the network interface device is selected from the groupconsisting of a dial-up modem, an ISDN card, a DSL modem, and a LANcard.
 8. The site controller of claim 1, wherein the logic is furtherconfigured to determine the one or more communication paths for each ofthe communication devices by receiving initialization commands from theplurality of communication devices.
 9. The site controller of claim 1,wherein the logic configured to manage communication with each of theplurality of communication devices comprises one or more look-up tablesresiding in a memory.
 10. The site controller of claim 1, wherein thelogic is further configured to receive a first message generated by oneof the plurality of communication devices via the second communicationnetwork, the first message comprising a first communication deviceidentifier associated with the one of the plurality of communicationdevices associated with one of the plurality of remote devices thatgenerated the first message and a predetermined function codecorresponding to a data signal provided by the one of the plurality ofremote devices associated with the one of the plurality of communicationdevices that generated the message.
 11. The site controller of claim 10,wherein the logic is further configured to determine, based on the firstcommunication device identifier, the one of the communication devicesthat generated the first data signal.
 12. The site controller of claim11, wherein the logic is further configured to translate the firstmessage into a second message configured for transmission to the hostcomputer via the first communication network.
 13. The site controller ofclaim 11, wherein the first message further comprises a secondcommunication identifier associated with an intermediate communicationdevice corresponding to the current communication path through which thefirst message was received by the transceiver.
 14. The site controllerof claim 13, wherein the logic is further configured to determine, basedon the second communication device identifier, the intermediatecommunication device.
 15. The site controller of claim 1, wherein theoperating status comprises information representative of whether theremote device is operational.
 16. The site controller of claim 1,wherein the site controller is further configured to maintain a databaseof operating statuses received from the remote devices for transmissionto a host computer upon receiving a request from the host computer. 17.A site controller for controlling communication with a host computerconnected to a first communication network and a plurality ofcommunication devices that define a second communication networkassociated with a plurality of remote devices that are to be monitoredand controlled by the host computer, wherein the second communicationnetwork comprises a first communication device associated with a firstremote device and a second communication device associated with a secondremote device, the site controller comprising: a means for communicatingwith the plurality of communication devices via the second communicationnetwork; a means for communicating with the host computer via the firstcommunication network; and a means for managing communication with thehost computer via a second communication protocol, wherein the sitecontroller is configured to poll the remote devices according to apredetermined schedule by transmitting a status message to one or moreof the remote devices requesting the remote device to transmit a messagecontaining current operating status of the remote device, wherein theoperating status comprises information indicative of a conditionmonitored or controlled by the remote device independent of the otherremote devices and communication devices, wherein the site controller isfurther configured to manage downstream communication from the sitecontroller to the plurality of communication devices in the secondcommunication network and up-stream communication from the plurality ofcommunication devices in the second communication network to the sitecontroller based upon a network map comprising one or more down-streamand up-stream communication paths between each communication device inthe plurality of communication devices and the site controller, andwherein the site controller is further configured to determine and storeupstream and downstream communication paths for each of the plurality ofcommunication devices in the second communication network.
 18. The sitecontroller of claim 17, wherein each of the plurality of communicationdevices are wireless communication devices, the plurality of wirelesscommunication devices being disposed throughout a geographic area suchthat the antenna patterns associated with the plurality of wirelesscommunication devices overlap to create a coverage area that defines thesecond communication network.
 19. The site controller of claim 17,wherein the first communication network is a wide area network and thesecond communication protocol comprises TCP/IP.
 20. The site controllerof claim 17, wherein the first communication protocol comprises a datapacket, the data packet comprising: a means for identifying intendedrecipients; a means for identifying the sender; a means for indicating acommand; a means for data transfer; a means for indicating potentialerror; a means for indicating a length of a packet; a means forindicating a total number of packets in a message; a means foridentifying a message; a means for alerting the recipients to anincoming packet; and a means for indicating an end of a packet.
 21. Thesite controller of claim 17, wherein the site controller is furtherconfigured to receive initialization commands from the plurality ofcommunication devices.
 22. The site controller of claim 17, wherein thesite controller is further configured to maintain a database ofoperating statuses received from the remote devices for transmission toa host computer upon receiving a request from the host computer.